Why my desk always faces the window

I went outside and managed to measure the moth (2 cm. wingspan) and take a few photos before he flew away. Because of the confusing background inside, I taped a couple of pieces of felt, the handiest thing available at the moment, to the inside of the window.

Moth on pink felt.

Moth on green felt, with shadow.

This last photo is not very good, but comparing it to the one on pink shows how transparent those wings are; you can see the pink or green background colour through them.

The moth is still unidentified. I'll head over to BugGuide as soon as possible.